There are many forms of banknote validation known in the art and there are numerous variants of conventional banknote validators.
An example of a prior art banknote validator is disclosed in EP-B-1,415,281. Here, the banknote validator comprises a housing including banknote validation sensor means, a banknote drive mechanism which circulates the banknote from a banknote input aperture, passed the banknote validation sensor means, to an underside section adjacent to stacking means and an attached cashbox for storing banknotes.
The banknote drive mechanism of EP-B-1,415,281 takes the form of a removable cassette including a drive motor and a pair of continuous drive belts which loop around the cassette.
A problem exists with the above mentioned prior art approach in that when a received banknote is transported around the drive mechanism to a position adjacent to the cashbox, the onboard processing means of the banknote validator cannot determine the position of the banknote prior to activation of a banknote stacking operation that urges the banknote into the cashbox. Consequently, a stacking operation may be instigated when a banknote is in an incorrect position, resulting in damage to the banknote or the occurrence of a mechanism jam.
In addition, a further issue arises with a conventional banknote validator as described in EP-B-1,415,281 in that if the banknote validator sensor means includes ultraviolet illumination for detecting visible fluorescence in banknotes, it is necessary to include additional elements into the sensor arrangement to facilitate the calibration of camera sensors. Also, EP-B-1,415,281 does not address the problem associated with banknote “strimming”, where a tape or string attached to the banknote is used to extract the banknote from the validator input aperture after the banknote has been successfully authenticated by the banknote validator sensor means.